( May 14, 2026, 1:15 PM EDT) -- WASHINGTON, D.C. — A partially split Federal Circuit U.S. Court of Appeals largely affirmed findings from the U.S. Patent Trial and Appeal Board’s (PTAB) decision finding that multiple claims of railroad collision-avoidance patents were invalid as obvious as per prior art; the panel reversed the PTAB’s finding that certain challenged claims survived, determining that the PTAB employed too narrow a claim construction on these claims....